Choosing the right mattress size affects your sleep quality, your bedroom layout, and what you spend on bedding and bed frames for years to come. This guide gives you the exact dimensions of every standard US mattress size — in inches, feet, and centimeters — plus side-by-side comparisons, room-size requirements, and clear recommendations for who each size is right for.
Every standard US mattress size, smallest to largest, with measurements in three units. Useful when you're cross-referencing bedding, bed frames, or international sizes.
| Mattress size | Inches (W × L) | Feet (W × L) | Centimeters (W × L) | Surface area |
|---|---|---|---|---|
| Twin (Single) | 38" × 75" | 3'2" × 6'3" | 97 × 191 cm | 2,850 sq in |
| Twin XL | 38" × 80" | 3'2" × 6'8" | 97 × 203 cm | 3,040 sq in |
| Full (Double) | 54" × 75" | 4'6" × 6'3" | 137 × 191 cm | 4,050 sq in |
| Full XL | 54" × 80" | 4'6" × 6'8" | 137 × 203 cm | 4,320 sq in |
| Queen | 60" × 80" | 5'0" × 6'8" | 152 × 203 cm | 4,800 sq in |
| Olympic Queen | 66" × 80" | 5'6" × 6'8" | 168 × 203 cm | 5,280 sq in |
| King (Eastern King) | 76" × 80" | 6'4" × 6'8" | 193 × 203 cm | 6,080 sq in |
| California King (Western King) | 72" × 84" | 6'0" × 7'0" | 183 × 213 cm | 6,048 sq in |
| Split King | 76" × 80" (2 × Twin XL) | 6'4" × 6'8" | 193 × 203 cm | 6,080 sq in |
The standard mattress sizes in the US are Twin, Full, Queen, King, and California King. Twin XL, Full XL, Olympic Queen, and Split King are regional or specialty variants of those standards.
Mattress size isn't just about sleeping space — it shapes your whole bedroom setup:
Start by thinking about who's using the bed and how much realistic clearance you need around it — then pick the size that fits.
The Twin mattress is the smallest standard size in the US lineup. Width: 38 inches (3'2" / 97 cm). Length: 75 inches (6'3" / 191 cm).
Ideal for: children and teens, bunk beds and daybeds, small guest rooms, trundles.
Pros: most affordable size, fits tight spaces, easy to move on delivery, widest bedding selection at the lowest prices.
Cons: too short for adults over 6 feet (Twin XL solves that), narrow for adult sleep beyond age 12 or so.
Minimum room size: 7 × 10 ft.
The Full mattress — also called a Double — measures 54" × 75" (4'6" × 6'3" / 137 × 191 cm). "Full" and "Double" are two names for the same size.
Ideal for: solo adult sleepers, college students, guest rooms, smaller bedrooms.
Pros: 16 inches wider than a Twin while keeping the same length; lower price than Queen or King; fits standard 10 × 10 ft bedrooms with room for furniture.
Cons: tight for two adults (only ~27 inches per person); 75-inch length is short for sleepers over 6 feet.
Minimum room size: 10 × 10 ft.
The Queen mattress is the most popular mattress size in the US. It measures 60" × 80" (5'0" × 6'8" / 152 × 203 cm) — wide enough for two adults to sleep comfortably without overwhelming a typical master bedroom.
Ideal for: couples, single adults who want more room, primary bedrooms, guest suites.
Pros: the widest selection of mattress models is built in Queen first; balanced cost vs. space; works in most master bedrooms; widely available bedding.
Cons: needs slightly more floor space than a Full; couples who co-sleep with kids or pets may eventually want a King.
Minimum room size: 10 × 11 ft (10 × 12 is more comfortable).
The King mattress (also called the Eastern King or Standard King) measures 76" × 80" (6'4" × 6'8" / 193 × 203 cm). It's 16 inches wider than a Queen — each person in a couple gets roughly the same sleep width as a Twin XL.
Ideal for: couples who want maximum sleeping space, sleepers who share a bed with children or pets, large master bedrooms.
Pros: the most personal space of any standard size; works well with Split King setups on adjustable bases when partners have different sleep preferences.
Cons: needs a 12 × 12 ft room minimum (ideally 13 × 13+); pricier mattress and bedding; harder to maneuver through narrow doorways and stairwells on delivery.
Minimum room size: 12 × 12 ft.
A good rule of thumb: leave at least 24 inches of clearance on each side of the bed and at the foot, so you can walk around the mattress comfortably and open dresser drawers without obstruction.
| Room size | Comfortable for |
|---|---|
| 9' × 10' | Twin or Twin XL |
| 10' × 10' | Full — comfortable fit with nightstands |
| 10' × 11' | Queen — fits with nightstands and a small dresser |
| 11' × 12' | Queen with room for a larger dresser and chair |
| 12' × 12' | King — the minimum room size for comfortable King fit |
| 13' × 13' or larger | King with full furniture flexibility, or California King for narrow rooms |
If you're torn between two sizes, measure your room and mark the mattress footprint on the floor with painter's tape. It's the single best way to avoid a return.
Lying down on a mattress for two minutes tells you more than any spec sheet. Our LA Mattress Store showrooms carry Twin, Full, Queen, King, and California King mattresses across every major construction type — memory foam, hybrid, latex, and innerspring — so you can compare sizes and feels side by side.
Every mattress comes with a 120-night comfort guarantee and financing options are available across all sizes.
Queen, at 60" × 80". It works for most couples, fits in most master bedrooms, and has the widest selection of mattress models built in that size first.
Technically yes, but each person gets only ~27 inches of width — less than a Twin. Most couples find a Queen significantly more comfortable for sharing a bed long-term.
Not comfortably. A King needs at least a 12 × 12 ft room to leave proper clearance on the sides and at the foot. In a 10 × 10 room, a Queen is a much better fit.
Nothing — they're two names for the identical 54" × 75" mattress size. "Double" is older terminology that some manufacturers and bed-frame makers still use.
The Olympic Queen (66" × 80") sits between them — 6 inches wider than a Queen and 10 inches narrower than a King. Selection is more limited than standard sizes, but it's a good middle option when a King won't fit.
A standard King is 76" × 80". A California King is 72" × 84" — 4 inches narrower and 4 inches longer. Choose California King if you're 6'2" or taller, or your room is long and narrow. Otherwise, a standard King has more shoulder room and a wider selection of bedding.
Yes. Twin XL (38" × 80") is the standard size in most US college dormitories. Confirm with your specific school before buying bedding, as some older dorms still use standard Twin.
Yes. King mattresses require a King-size frame, and most King frames include a center support leg to prevent the foundation from sagging. Don't try to make a Queen frame work with a King mattress.
No. UK and European bed sizes use different dimensions — a UK "king" is 60" × 78", roughly equivalent to a US Queen. Always cross-check by exact dimensions in centimeters when buying internationally.
No. King sheets are 16 inches wider than Queen sheets and won't tuck properly. Cal King sheets are different again — longer but narrower than standard King. Always check the size label before buying bedding.
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